What about pulling from Zahn?

Star Wars, Ahoska: Survivor’s Quest

Here is a summary of the Legends novel Survivor’s Quest:

The Chiss have found the remains of the colonization and exploratory vessel Outbound Flight, which had been destroyed by Grand Admiral Thrawn many years previous. Now, the Chiss wish to hand over their find to the New Republic, and Luke and Mara join the odd group which will visit the site of the tragedy. As they voyage deeper into space, Luke and Mara grow more uneasy. Occurrences of sabotage and theft only serve to deepen their suspicions. On top of that, Mara begins to feel torn between her duty to the New Republic and her troubled respect for the Empire.

Here is a summary of the fanedit:

Morgan Elsbeth has found the remains of the Chimaera, which had gone missing with Grand Admiral Thrawn aboard many years previous. Now, Ahsoka Tano and her apprentice Sabine Wren wish to warn the New Republic of this threat. Ahsoka and Sabine race against Morgan and her odd group to the potential site of the ship. As they voyage deeper into space, Ahsoka and Sabine grow more uneasy. Occurrences of mercenaries and visions in the Force only serve to deepen their mission. On top of that, Sabine begins to feel torn between her duty to the New Republic and her quest to find her lost friend.

The Survivor could be referring to